Electric Water Pump vs Electric Drive kit

[jeep cj7 304]

alright I finally decided to switch to electric water pump, should i go with a self contained electric water pump like the meziere or csr, or should I go the cheaper way of external drive from a water pump drive kit. it's either $350 for the self contained or $125 for the drive kit.

P.S. looks are a big consideration for my engine.

 

[CJ]

IMHO - Stay away from both - especially the electric drive. They are not rated for street or off-road usage and will most likely bite you when you least can afford it. This comes from personal experience with the electric drive unit - used with a drag car.

We had a drag car that we occasionally drove on the street that had an electric drive kit and it was a nightmare. This was on a SBC. It barely kept the car cool 1/4 mile at a time and never worked for the street. The electric motor RPM doesn't change to flow more water when you need it.

The Meziere pump flows per its specs, 35 - 40 gal per minute and is rated for mild street and drag race use. That means in disclaimer terms - use on a street car at your own risk... These things are designed to only keep a vehicle cool for 1320 feet and then circulate between rounds as the engine is not producing more heat.

There is a reason race cars that run continuously (go round and round), off-road racers, NASCAR and countless others have never gone electric. They just can't handle the continuous flow demands.

Now, could you get by. Maybe... I would not do it. If you want to spend $300 bucks and engine looks are important - get a nice pulley system. You will be much happier in the end... IMHO!

 

[jeep cj7 304]

alright, that makes it easy. Thanks. I was worried that it would shake apart anyway. Because lets face it my jeep isnt the smoothest on or off road. Alright so instead i might throw on some roller rockers or wait and get some head porting done.

 

[CJ]

alright, that makes it easy. Thanks. I was worried that it would shake apart anyway. Because lets face it my jeep isnt the smoothest on or off road. Alright so instead i might throw on some roller rockers or wait and get some head porting done.

Sounds like a plan... What heads do you have on your 304? The dogleg ports that are standard on AMC are some great flowing heads to begin with. There isn't allot to do to them to make them flow better. Basically a little polishing to unshroud the valves and some port matching.

To do a half way decent port match, get a good set of gaskets and use them to scribe the port shape on the head, blend to the gasket scribe and do the same for the intake and exhaust.

You don't want to do much to the combustion area or remove much material in the intake runners unless you have a flow bench.

If you want to check flow and match the cylinders... I have made a flow bench before - we can even walk through that if you would like...

Speaking of rollers. Did you see my review of the Harland Sharp RR's? They really shouldn't be used without screw in studs being installed. Need to be careful if you decide to change the ratio as well...

 

[projectcrawler]

I was just looking into getting my heads ported when I read this thread. Keep us informed on what you find.

 

[jeep cj7 304]

I might polish my runners, but what type size studs did you use for your rockers. I'm not sure if I've got 7/16th or 3/8ths inch bolts, nor am I sure if they are dogleg, does that mean the exhaust port, because mine are L shaped.

 

[CJ]

I might polish my runners, but what type size studs did you use for your rockers. I'm not sure if I've got 7/16th or 3/8ths inch bolts, nor am I sure if they are dogleg, does that mean the exhaust port, because mine are L shaped.

If you have the correct 1976 heads, you have 3/8ths studs as stock (I think - I'm checking this). To put screw in studs in the heads the stud seats need to be milled flat and then threaded. I have 7/16 in mine. If you don't want to go to the added expense of a true roller rocker arm, there are many great direct replacement roller tipped rockers for the AMC V8. A much cheaper alternative and if you aren't going to be turning ultra high revs - they work just fine.

Yes, the exhaust port looks like a 'L'. I think it was 70 when AMC went to the dogleg exhaust port. The flow of this head (exhaust side) was about 50% better then the standard head before that.

 

[jeep cj7 304]

alright so they are dogleg and I never plan to go too high revs. so I guess I'll just look for stamped rockers. It'll be much easier. One more question, what all would need to be changed to run 8 pounds of boost, I've heard all that needs to happen is change the pistons and you'll be set.

 

[CJ]

Stock pistons for a 304 generate 8.4 to 1 compression. That is low enough for that amount of boost. I would be much more worried about cast vs forged then the compression ratio...